JP5333727B2 - Fuel cell separator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deterioration of rigidity of a separator outer periphery portion corresponding to a line of a seal part to prevent gas leakage in an MEA, and attain thinness of the separator and simplification of positioning of an intermediate plate. <P>SOLUTION: The fuel cell separator has a pair of metallic electrode plates 12, 14 facing each other and an intermediate plate 13 made of plastic which is interposed and laminated between the pair of electrode plates 12, 14. The separator has a seal part 42 which is installed at the outer periphery portion of gas passage formation parts 40, 41 of the MEA 30 and between the catalyst electrode and electrode plates 12, 14 of the MEA 30 and maintains gas sealing property in the gas passage formation parts 40, 41 by contacting the electrode plates 12, 14. A reinforcing part 51 is provided at intermediate plate 13 portion, or its outer periphery, corresponding to a line SL which goes around the outer periphery portion of a separator and rigidity of the separator outer periphery portion is enhanced. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a fuel cell separator that constitutes a fuel cell by being laminated with MEA (Membrane Electrode Assembly).

Conventionally, as this kind of technology, for example, there is one described in Patent Document 1.
This is a metal first and second plate, and a plate sandwiched between these two plates, and penetrates in a part of the region overlapping the electrolyte layer and the electrode layer during lamination, And a third plate (intermediate plate) that forms a refrigerant flow path through which the refrigerant flows between the first and second plates. The flow rate of the refrigerant in the refrigerant flow channel is arranged in the refrigerant flow channel so that the flow rate of the refrigerant in the temperature distribution in the separator surface during power generation of the fuel cell becomes higher as the temperature becomes higher. It is said that it has a flow velocity adjustment part which adjusts (refer to patent documents 1).

JP 2007-109425 A

According to the above prior art, there is an advantage that the internal temperature of the fuel cell can be equalized in the cell plane when the refrigerant is circulated inside the fuel cell, but the following problems remain.
That is, in the above prior art, a laminate resin having a seal layer and a heat-resistant resin layer may be used for the intermediate plate, but such a laminate resin is more rigid than the first and second plates made of metal. Is low. In addition, on the outer peripheral side of the intermediate plate made of the laminate resin, a plurality of manifold holes through which a cooling medium such as water (gas) such as air (oxygen) or hydrogen, or water flows are arranged side by side. Therefore, the outer peripheral portion of the intermediate plate has a very narrow and long structure, and the thickness is thin. Therefore, the rigidity in that portion is extremely low.
On the other hand, since the fuel cell has a structure in which a large number of such separators and single cells (MEA and gas flow path forming part) are arranged, these are fastened with a constant load. At this time, the gas from the MEA Since the load is also distributed to the seal portion (gasket) for preventing leakage at the outer peripheral portion, the load is easily applied on the seal line (gasket line).

As described above, in the separator using the laminate resin for the intermediate plate, the rigidity of the entire separator is lower than that of the separator constituted only by the metal plate, but the rigidity required particularly in the outer peripheral portion of the separator corresponding to the seal line is reduced. If it is not ensured, appropriate load distribution cannot be expected, and there is a risk of causing a short circuit due to a decrease in gas sealability or a deviation of the seal portion. For this reason, it has become a factor that hinders further thinning of the separator that can be achieved when it has the required rigidity.
Further, since the rigidity at the outer peripheral portion of the intermediate plate is extremely low, the manifold hole or the like disposed in the intermediate plate is caused by the reaction force of the seal portion due to the fastening load when a large number of pairs of separators and single cells are fastened. There is a possibility that the flow path of the gas and the cooling medium may be deformed to cause pressure loss variation. For this reason, the positioning of the intermediate plate has to be performed carefully, which is a troublesome operation.

  The present invention can prevent a decrease in rigidity at the outer peripheral portion of the separator corresponding to the seal portion line for preventing gas leakage in the MEA, and can further reduce the thickness of the separator and simplify the positioning of the intermediate plate. It is an object to provide a separator for an automobile.

The said subject is solved by making the separator for fuel cells into the structure of each following aspect.
As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the present invention, and the technical features described in this specification and combinations thereof should not be construed as being limited to those described in the following sections. . In addition, when a plurality of items are described in one section, it is not always necessary to employ the plurality of items together, and it is also possible to take out only a part of the items and employ them.

Of following sections (1) term in claim 1, (2) term in claim 2, each corresponding.

(1) A fuel cell separator that partitions a plurality of membrane-electrode assemblies constituting a fuel cell, and is made of a pair of opposing metal electrode plates and a resin sandwiched and laminated between the pair of electrode plates Comprising an intermediate plate, provided on the outer periphery of the gas flow path forming part between the catalyst electrode of the membrane-electrode assembly and the electrode plate, and on the outer periphery of the membrane-electrode assembly, A reinforcing portion is provided on the intermediate plate portion corresponding to a line that goes around the outer peripheral portion of the separator or a peripheral portion of the sealing portion that keeps the gas sealing property in the gas flow path forming portion by contacting the plate, and the reinforcing portion Is formed continuously or intermittently on the outer periphery of the separator along the line, and the reinforcing portion is embedded in the intermediate plate. Data.
The intermediate plate is a plate that is sandwiched and stacked between a pair of opposed electrode plates to form a refrigerant flow path.
The seal part line (seal line) is a line where the seal part comes into contact with the electrode plate, and a set of a set of a number of fuel cell separators and single cells (membrane-electrode assembly and gas flow path forming part). It is a part that sometimes receives the reaction force of the seal part, and the reinforcing part increases the rigidity of this part.
The dimension (width of the reinforcing part) in the direction intersecting the direction along the seal line of the reinforcing part is variously set in consideration of the material of the reinforcing part, the material of the intermediate plate, and the like.
Intermittent includes all forms that are not continuous, and various dimensions are set in the direction along the seal line of the reinforcing part that is intermittent (the length of the reinforcing part alone), the mutual interval between the reinforcing parts, and the like.
(2) The fuel cell separator according to (1), wherein the reinforcing portion is made of a metal material.
Examples of the metal material include metal materials having high corrosion resistance such as stainless steel and titanium.

According to the invention described in the item (1), it is possible to prevent a decrease in rigidity in the outer peripheral portion of the separator corresponding to the line of the seal portion for preventing gas leakage in the membrane-electrode assembly. Therefore, it is possible to further reduce the thickness of the separator and to simplify the positioning of the intermediate plate, which has hitherto been hindered by the decrease in rigidity at the separator outer periphery.
Moreover, the arrangement | positioning form of the reinforcement part along a seal line can be set variously as needed.
Further, there is no restriction on the dimension setting of the reinforcing portion for maintaining the sealing performance in the intermediate plate when the reinforcing portion directly contacts the electrode plate.
According to the invention described in the item (2), the metal material is easily available and can be easily processed, but the effect of preventing the decrease in rigidity at the outer peripheral portion of the separator is great, and the cost effectiveness is excellent.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.
FIG. 1 is a schematic cross-sectional view of an example of a fuel cell to which the present invention is applied.
As shown in the figure, the fuel cell includes a laminated body in which a separator 10, an MEA (membrane electrode assembly) 30, and gas flow path forming portions 40 and 41 are sequentially laminated.
In this case, the separator 10 is composed of three layers: a cathode side plate 12 forming one electrode plate, an intermediate plate 13 made of resin, and an anode side plate 14 forming the other electrode plate. The MEA 30 and the gas flow path forming portions 40 and 41 form a single cell 60 that is a unit of power generation, but the separator 10 is disposed between the single cells 60 and has a refrigerant flow therein. A path 18 is formed. The refrigerant refers to a cooling medium such as water.
A fuel cell is configured by repeatedly laminating units having such a single cell 60 and separator 10.

  2 is a schematic plan view of the cathode side plate 12, the intermediate plate 13, and the anode side plate 14 constituting the separator 10 in FIG. 1, wherein (a) is the cathode side plate 12, (b) is the intermediate plate 13, (C) shows the anode side plate 14, respectively. FIG. 1 shows a cross section in the short direction of a fuel cell having a rectangular planar shape, and the cross-sectional position is represented by a line II in FIG. 2A.

  As shown in FIGS. 2A to 2C, each of the plates 12 to 14 constituting the separator 10 is made of a rectangular thin plate having substantially the same outer shape and dimensions. Each of the plates 12 to 14 has a plurality of hole portions 20 to 25 that are elongated along the side at positions corresponding to each other on the outer peripheral portion. When the separator 10 and the single cell 60 are stacked to assemble the fuel cell, the plurality of holes 20 to 25 form a manifold that penetrates the fuel cell inside in the stacking direction and through which a predetermined fluid flows.

That is, in the vicinity of a predetermined one side corresponding to each of the plates 12 to 14, a plurality of, in the illustrated example, six holes 20 are provided along this side, and each of the plates 12 to 14 has the predetermined predetermined side. In the vicinity of the side facing one side, a plurality of, in the illustrated example, six hole portions 21 are provided along this side. In this case, the hole 20 forms an oxidizing gas supply manifold through which oxidizing gas supplied to the electrochemical reaction flows, and the hole 21 forms an oxidizing gas discharge manifold into which oxidizing gas supplied to the electrochemical reaction flows. To do.
Note that the oxidizing gas is a gas containing oxygen, and air is used here.

Two holes 22 and 23 are provided in the vicinity of the other side of each of the plates 12 to 14 along this side. In this case, a hole 22 is provided on the side where the hole 20 is provided, and a hole 23 is provided on the side where the hole 21 is provided.
The hole 22 forms a refrigerant supply manifold through which the refrigerant distributed to the refrigerant flow path 18 in the separator 10 flows, and the hole 23 is a fuel gas discharge manifold into which the fuel gas used for the electrochemical reaction flows. Form.
For example, an antifreeze or air is used as the refrigerant. The fuel gas is a gas containing hydrogen, and hydrogen gas is used here.

Two holes 24 and 25 are provided in the vicinity of the side facing each other side of each of the plates 12 to 14 along this side. In this case, a hole 24 is provided on the side where the hole 20 is provided, and a hole 25 is provided on the side where the hole 21 is provided.
The hole 24 forms a fuel gas supply manifold through which fuel gas to be subjected to an electrochemical reaction flows, and the hole 25 forms a refrigerant discharge manifold into which the refrigerant discharged from the refrigerant flow path 18 in the separator 10 flows. Form.
In addition, the code | symbols 20-25 attached | subjected to the hole part were also attached | subjected also to the corresponding manifold, respectively for convenience.

  The cathode side plate 12 includes a plurality of elongated holes 26 and 27 in addition to the holes 20 to 25 on the outer periphery thereof. In this case, the hole 26 is provided in the vicinity of the hole 20 corresponding to each of the plurality of holes 20, and is formed in parallel to the hole 20 inside the hole 20. The hole portion 27 is provided in the vicinity of the hole portion 21 corresponding to each of the plurality of hole portions 21, and is formed in parallel to the hole portion 21 inside the hole portion 21.

In addition to the holes 20 to 25 formed in the outer peripheral portion, the intermediate plate 13 is formed with a refrigerant flow path forming portion 15 that is a substantially square hole penetrating the central portion excluding the outer peripheral portion. . The refrigerant flow path forming portion 15 forms a space that becomes the refrigerant flow path 18 when the intermediate plate 13 is sandwiched between the cathode side plate 12 and the anode side plate 14. Further, in the intermediate plate 13, the holes 20, 21, 23, 24 have shapes different from those of the other plates 12, 14, and the holes 20, 21, 23, 24 are located on the plate center side. The side has a shape including a plurality of extending portions (gas supply / discharge passages) that extend toward the center of the plate. The plurality of extending portions of the hole portions 20, 21, 23, and 24 are referred to as communication portions 70, 71, 73, and 74, respectively.
The intermediate plate 13 includes a plurality of through holes (refrigerant supply / discharge passages) 72 that allow the hole 22 and the refrigerant flow path forming portion 15 to communicate with each other. The plurality of through holes 72 are formed in parallel to each other so as to communicate between the hole 22 and the refrigerant flow path forming unit 15 in parallel with the long side direction of the intermediate plate 13. Further, the intermediate plate 13 includes a plurality of through holes (refrigerant supply / discharge passages) 75 that communicate between the hole 25 and the refrigerant flow path forming portion 15 in the same manner as the through hole 72.

  The anode side plate 14 includes holes 28 and 29 in addition to the holes 20 to 25 on the outer periphery thereof. In this case, the hole 28 is an elongated hole provided in the vicinity of the hole 23 and formed in parallel to the hole 23 inside the hole 23. The hole 29 is an elongated hole formed in the vicinity of the hole 24 and formed in parallel to the hole 24 inside the hole 24.

The hole portion 26 provided in the cathode side plate 12 and the communication portion 70 provided in the intermediate plate 13 form the gas flow path through which the oxidizing gas flowing through the oxidizing gas supply manifold 20 passes through the inside of the separator 10. An oxidizing gas supply path that leads to the surface of the separator 10 in which the portion 40 is disposed is formed. And the hole part 27 provided in the cathode side plate 12 and the communication part 71 provided in the intermediate | middle plate 13 pass through the inside of the separator 10 from the separator 10 surface in which the gas flow path formation part 40 was arrange | positioned. Then, an oxidizing gas discharge passage for leading the oxidizing gas to the oxidizing gas discharge manifold 21 is formed.
Further, the hole 29 provided in the anode side plate 14 and the communication part 74 provided in the intermediate plate 13 form a gas flow path for the fuel gas flowing through the fuel gas supply manifold 24 through the inside of the separator 10. A fuel gas supply path that leads to the surface of the separator 10 in which the portion 41 is disposed is formed. And the hole part 28 provided in the anode side plate 14 and the communication part 73 provided in the intermediate | middle plate 13 pass through the inside of the separator 10 from the separator 10 surface in which the gas flow path formation part 41 was arrange | positioned. Then, a fuel gas discharge passage for guiding the fuel gas to the fuel gas discharge manifold 23 is formed.

The cathode side plate 12 and the anode side plate 14 are made of a thin plate material made of a conductive metal having high corrosion resistance such as stainless steel or titanium.
The intermediate plate 13 is formed of a laminate resin including a seal layer and a heat resistant resin layer, but may be formed of other materials. The holes 20 to 29 are formed by punching.
When forming the separator 10, the holes 20 to 25 are aligned and aligned in the order of the cathode side plate 12, the intermediate plate 13, and the anode side plate 14, and the plates 12 to 14 are sealed by heat bonding. It is joined.

The MEA 30 constituting the single cell 60 includes an electrolyte layer and a catalyst electrode layer formed on the electrolyte layer. The illustrated fuel cell is a solid polymer fuel cell, the electrolyte layer is made of a solid polymer material, and the catalyst electrode layer is made of a catalyst that promotes an electrochemical reaction.
The gas flow path forming portions 40 and 41 are made of a plate material having conductivity and gas permeability, and a layer made of a carbon porous body is disposed on the surface of the MEA 30 in contact with the gas flow path forming portions 40 and 41. Has been.
The space formed inside the gas flow path forming portions 40 and 41 forms a flow path in the single cell 60 of the gas used for the electrochemical reaction. That is, the gas flow path forming unit 40 disposed between the MEA 30 and the cathode side plate 12 forms an in-single cell oxidizing gas flow path through which the oxidizing gas flows. In addition, a gas flow path forming portion 41 disposed between the MEA 30 and the anode side plate 14 (refers to the anode side plate 14 of the separator 10 (not shown) stacked below the single cell 60 shown). The fuel gas flow path in the single cell through which the fuel gas flows is formed.

Between the adjacent separators 10 and on the outer peripheral portions of the MEA 30 and the gas flow path forming portions 40 and 41, for example, a seal portion 42 made of a resin material such as silicon rubber, butyl rubber, or fluorine rubber is provided integrally with the MEA 30. Yes.
Although the detailed illustration is omitted, the seal portion 42 is manufactured, for example, by injection molding a resin material with the outer peripheral end portion of the MEA 30 portion facing the cavity of a mold. Thereby, MEA30 and the seal part 42 are joined without gap, and it can prevent that oxidizing gas and fuel gas leak from a joined part.
FIG. 3 is a schematic plan view of the seal portion 42 formed integrally with the MEA 30.
The seal part 42 in the drawing has a rectangular shape whose outer shape and dimensions are substantially the same as those of the separator 10, and the holes 20 to 25 are formed in the same manner as the separator 10.
In FIG. 3, the hole 22 forming the refrigerant supply manifold is “refrigerant inlet”, the hole 25 forming the refrigerant discharge manifold is “refrigerant outlet”, and the hole 24 forming the fuel gas supply manifold is “H ₂ inlet”. "hole 23 forming a fuel gas discharge manifold has a" H ₂ outlet ".

  In FIG. 1, when the separator 10 and the single cell 60 are manufactured, the cathode side plate 12 is in contact with the gas flow path forming portion 40, and the anode side plate 14 is in contact with the gas flow path forming portion 41 (above the separator 10 shown in the figure). A fuel cell is manufactured by alternately laminating the separators 10 and the single cells 60 so as to be in contact with the gas flow path forming portions 41 of the single cells 60 (not shown).

In the fuel cell as described above, when the oxidizing gas is supplied to the oxidizing gas supply manifold 20, the oxidizing gas passes through the oxidizing gas supply path composed of the communication portion 70 and the hole portion 26 in each separator 10, It is distributed to the oxidizing gas flow path in the single cell formed by the flow path forming unit 40.
The distributed oxidizing gas flows through the oxidizing gas flow path in the single cell toward the oxidizing gas discharge manifold 21 while being subjected to an electrochemical reaction. The direction of the oxidizing gas flow in the oxidizing gas flow path in the single cell is indicated by an arrow A in FIG. 3 as the direction with respect to the MEA 30 surface.
The oxidant gas that has passed through the oxidant gas flow path in the single cell is discharged to the oxidant gas discharge manifold 21 through the oxidant gas discharge path including the hole 27 and the communication part 71 in the separator 10. The state of the inflow and outflow of the oxidizing gas in the vicinity of the manifold is indicated by arrows a in FIG.

When the refrigerant is supplied to the refrigerant supply manifold 22, the refrigerant is distributed to the refrigerant flow path 18 through the plurality of through holes 72 of the intermediate plate 13 in each separator 10.
FIG. 4 is a cross-sectional view in the longitudinal direction of the fuel cell shown in FIG. 1, and the cross-sectional position is represented by the IV-IV line in FIG. 2 (a).
In FIG. 4, the state in which the refrigerant flowing through the refrigerant supply manifold 22 flows into the refrigerant flow path 18 through the plurality of through holes 72 (see FIG. 2B) is indicated by arrows c.
The refrigerant distributed through the through hole 72 flows through the refrigerant flow path 18 toward the refrigerant discharge manifold 25.
The direction of the flow of the refrigerant in the refrigerant flow path 18 is indicated by an arrow D in FIG. 3 as the direction with respect to the MEA 30 surface. The refrigerant flowing in the refrigerant flow path 18 is discharged to the refrigerant discharge manifold 25 through the through hole 75 of the intermediate plate 13 shown in FIG.

In such a fuel cell, when the fuel gas is supplied to the fuel gas supply manifold 24, the fuel gas flows through the fuel gas supply path including the communication portion 74 and the hole 29 in each separator 10. It is distributed to the fuel gas flow path in the single cell formed by the path forming part 41.
A state in which the fuel gas flows from the fuel gas supply manifold 24 into the fuel gas flow path in the single cell is indicated by an arrow O in FIG.
The distributed fuel gas flows through the fuel gas flow path in the single cell toward the fuel gas discharge manifold 23 while being subjected to an electrochemical reaction. The direction of the flow of the fuel gas in the fuel gas flow path in the single cell is indicated by an arrow O in FIG. 3 as the direction with respect to the MEA 30 surface.
The fuel gas that has passed through the fuel gas flow path in the single cell is discharged to the fuel gas discharge manifold 23 through the fuel gas discharge path including the hole portion 28 and the communication portion 73 shown in FIG.

The separator for a fuel cell according to the present invention is a separator for partitioning a plurality of MEAs constituting the fuel cell, and as shown in FIGS. The present invention relates to a separator 10 that forms a refrigerant flow path 18 by sandwiching and laminating a resin intermediate plate 13 with an anode side plate 14.
And as shown in FIG.1 and FIG.4, the gas flow path formation part 40, provided in the outer peripheral part of MEA30 and the gas flow path formation parts 40 and 41, and contacting with the cathode side plate 12 and the anode side plate 14, In the separator 10 provided with the sealing portion 42 for maintaining the gas sealing performance in 41, the following configuration is provided.

Basically, the gas sealability is maintained by the seal portion 42, and a reinforcing portion is provided in the intermediate plate 13 portion corresponding to the line of the seal portion 42 that goes around the outer periphery of the separator. Embodiments will be described below.
5 and 6 are explanatory views of an embodiment of the fuel cell separator according to the present invention. 5 is a plan view showing an arrangement example of the reinforcing portions 51 in the intermediate plate 13, and FIG. 6 is an enlarged sectional view taken along the line VI-VI in FIG. 5. 7 to 9 are enlarged sectional views taken along line VI-VI in FIG. 5 in an example different from FIG.

As illustrated in FIG. 5, the reinforcing portion 51 is provided in the intermediate plate 13 portion corresponding to the line (seal line) SL of the seal portion 42 that goes around the separator outer periphery.
Specifically, the reinforcing portion 51 is formed around the separator outer periphery along the seal line SL. The reinforcing portion 51 may be formed continuously around the outer peripheral portion of the separator. However, if formed in this way, the intermediate plate 13 is divided into two in the inner and outer peripheral directions at the outer peripheral portion. If the reinforcing portion 51 is formed intermittently along the seal line SL as in the illustrated example, the intermediate plate 13 can be prevented from being divided into two as described above. According to such intermittent formation of the reinforcing portions 51, it is possible to form one intermediate plate 13 in which the inner and outer peripheral portions are connected in the portion between the adjacent reinforcing portions 51.

In the example shown in FIG. 6, the reinforcing portion 51 is provided by adhering to the cathode side plate 12 and the anode side plate 14. However, as illustrated in FIG. 7, the reinforcing portion 51 is embedded in the intermediate plate 13. May be. According to this, the trouble of bonding the reinforcing portion 51 to the plates 12 and 14 can be saved. Further, there is no restriction on the dimension setting of the reinforcing portion 51 as will be described later for maintaining the sealing performance in the intermediate plate 13 when the reinforcing portion 51 directly contacts the plates 12 and 14.
In the example shown in FIGS. 6 and 7, for example, a metal material is used as the reinforcing portion 51, but glass fiber or carbon fiber or the like is reinforced at a portion corresponding to the position where the reinforcing portion 51 is provided in FIGS. 6 and 7. The reinforcing plate 51 may be formed as the reinforcing plate 51 by mixing the fibers for forming the intermediate plate 13.
In addition, when using a metal material as the reinforcement part 51, the metal material which has high corrosion resistance, such as stainless steel or titanium, is mentioned as a good example.

Further, as illustrated in FIG. 9, the reinforcing portion 51 may be formed on any one of the pair of electrode plates 12 and 14, for example, the anode side plate 14. That is, a plate outer peripheral end protrusion is formed on the anode side plate 14 so as to straddle the outer peripheral end of the intermediate plate 13 and abut the surface facing the anode side plate 14 of the cathode side plate 12 which is the other electrode plate. The unit 51 may be used.
In any case, the reinforcing portion 51 is formed of a material having higher rigidity than the intermediate plate 13.

According to such a configuration, the reaction force of the seal portion 42 (see FIGS. 1 and 4) is applied when fastening a portion corresponding to the seal line SL on the outer peripheral portion of the separator, in other words, a set of a large number of separators and single cells. The rigidity of the separator outer peripheral portion to be received is enhanced by providing the reinforcing portion 51 on the intermediate plate 13 portion or on the outer periphery thereof.
According to the example of FIGS. 7 and 8 including the reinforcing portion 51 in the intermediate plate 13, the rigidity of the intermediate plate 13 itself is enhanced at the outer peripheral portion. On the other hand, according to the examples of FIGS. 6 and 9 in which the intermediate plate 13 does not include the reinforcing portion 51, the rigidity of the intermediate plate 13 itself cannot be increased. Increased by providing 51.

6 and 9, when the reinforcing portion 51 is provided between the plates 12 and 14 without partially interposing the intermediate plate 13, the reinforcing portion 51 is directly connected to the plate 12. 14, the sealing performance of this portion may not be maintained, and therefore the reinforcing portion 51 is dimensioned as follows.
In other words, the dimension (height dimension) of the reinforcing portion 51 in the direction of laminating the plates 12 to 14 is set so that when the three plates 12 to 14 are laminated and assembled, the respective laminating surfaces of the intermediate plate 13 and the plates 12 and 14 are The dimensions are set so as to be in close contact with the surfaces of the plates 12 and 14 while maintaining the sealing performance. Basically, the height dimension of the reinforcing portion 51 does not exceed the thickness of the intermediate plate 13 (dimension in the plate stacking direction).

As described above, according to the present embodiment, the rigidity in the outer peripheral portion of the separator is increased by providing the reinforcing portion 51. In particular, in the examples of FIGS. 7 and 8, the rigidity of the intermediate plate 13 itself is increased at the outer periphery thereof.
As described above, when the required rigidity is not ensured in the outer peripheral portion of the separator corresponding to the seal line SL, the constant added to arrange a large number of pairs of the separator 10 and the single cells 60 (see FIGS. 1 and 4). Proper load distribution cannot be expected for the fastening load. For this reason, there exists a possibility of causing the short circuit by a gas-seal property fall or a seal | sticker part shift | offset | difference, and prevented further thinning of the separator 10 which can be achieved when it has required rigidity.
According to the above-described embodiment, the required rigidity is given to the outer peripheral portion of the separator by the reinforcing portion 51, so that the separator 10 can be further thinned.

Further, since the rigidity of the outer peripheral portion of the intermediate plate 13 is extremely low, the hole portion that forms the manifold disposed in the intermediate plate 13 by the reaction force of the seal portion 42 (see FIGS. 1 and 4) due to the fastening load. Gases such as 20 to 25 and the flow path of the cooling medium may be deformed to cause pressure loss variation. For this reason, the positioning of the intermediate plate 13 has to be performed carefully, which is a troublesome operation.
According to the above-described embodiment, since the required rigidity is given to the outer peripheral portion of the separator by the reinforcing portion 51, the positioning of the intermediate plate 13 can be simplified.

Note that the seal line SL does not necessarily have a shape along the outer shape of the separator (plates 12 to 14) as shown in FIG. There is also a separator 10 that draws a seal line SL as shown in FIG.
Also in such a separator 10, the reinforcing portion 51 is provided continuously or intermittently on the intermediate plate 13 portion corresponding to the illustrated seal line SL that goes around the outer periphery of the separator or on the outer periphery thereof. Needless to say, the same effect can be obtained.

It is a schematic sectional drawing of an example of the fuel cell to which this invention is applied. It is a schematic plan view of each plate which comprises the separator in FIG. It is a schematic plan view of the seal part integrally formed with MEA. It is sectional drawing of the longitudinal direction of the fuel cell shown in FIG. In the explanatory view of one embodiment of the separator for fuel cells concerning the present invention, the example of arrangement of a reinforcement part is shown. It is the VI-VI line expanded sectional view in FIG. It is VI-VI line expanded sectional view about the reinforcement part which concerns on a 2nd example. It is VI-VI line expanded sectional view about the reinforcement part which concerns on a 3rd example. It is VI-VI line expanded sectional view about the reinforcement part which concerns on a 4th example. It is a figure which shows the other example of arrangement | positioning (another example of a seal line shape) of a reinforcement part.

Explanation of symbols

  10: Separator, 12: Cathode side plate (electrode plate), 13: Intermediate plate, 14: Anode side plate (electrode plate), 30: MEA (membrane-electrode assembly), 40, 41: Gas flow path forming part, 42: seal part, 51: reinforcement part, 60: single cell, SL: seal line.

Claims (2)

A separator for a fuel cell that partitions a plurality of membrane-electrode assemblies constituting the fuel cell,
A pair of opposing metal plates and a resin intermediate plate sandwiched and laminated between the pair of electrode plates,
Provided on the outer periphery of the gas flow path forming portion between the catalyst electrode of the membrane-electrode assembly and the electrode plate, and on the outer periphery of the membrane-electrode assembly, and by contacting the electrode plate, A reinforcing portion is provided on the intermediate plate portion or the outer periphery thereof corresponding to a line that goes around the outer periphery of the separator of the seal portion that maintains the gas sealing property in the gas flow path forming portion,
This reinforcing part is formed continuously or intermittently on the outer periphery of the separator along the line,
A fuel cell separator, wherein the reinforcing portion is embedded in the intermediate plate.   The fuel cell separator according to claim 1, wherein the reinforcing portion is made of a metal material.

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